grdev.h revision 650c5444273993f969b9cd7df9add6ab2df0414e
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright (C) 2014 David Herrmann <dh.herrmann@gmail.com>
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
/*
* Graphics Devices
* The grdev layer provides generic access to graphics devices. The device
* types are hidden in the implementation and exported in a generic way. The
* grdev_session object forms the base layer. It loads, configures and prepares
* any graphics devices associated with that session. Each session is totally
* independent of other sessions and can be controlled separately.
* The target devices on a session are called display. A display always
* corresponds to a real display regardless how many pipes are needed to drive
* that display. That is, an exported display might internally be created out
* of arbitrary combinations of target pipes. However, this is meant as
* implementation detail and API users must never assume details below the
* display-level. That is, a display is the most low-level object exported.
* Therefore, pipe-configuration and any low-level modesetting is hidden from
* the public API. It is provided by the implementation, and it is the
* implementation that decides how pipes are driven.
*
* The API users are free to ignore specific displays or combine them to create
* larger screens. This often requires user-configuration so is dictated by
* policy. The underlying pipe-configuration might be affected by these
* high-level policies, but is never directly controlled by those. That means,
* depending on the displays you use, it might affect how underlying resources
* are assigned. However, users can never directly apply policies to the pipes,
* but only to displays. In case specific hardware needs quirks on the pipe
* level, we support that via hwdb, not via public user configuration.
*
* Right now, displays are limited to rgb32 memory-mapped framebuffers on the
* primary plane. However, the grdev implementation can be easily extended to
* allow more powerful access (including hardware-acceleration for 2D and 3D
* compositing). So far, this wasn't needed so it is not exposed.
*/
#pragma once
#include <drm_fourcc.h>
#include <inttypes.h>
#include <stdbool.h>
#include <stdlib.h>
#include <systemd/sd-event.h>
#include "util.h"
typedef struct grdev_display_target grdev_display_target;
typedef struct grdev_display grdev_display;
typedef struct grdev_event grdev_event;
typedef struct grdev_session grdev_session;
typedef struct grdev_context grdev_context;
enum {
/* clockwise rotation; we treat this is abelian group Z4 with ADD */
GRDEV_ROTATE_0 = 0,
GRDEV_ROTATE_90 = 1,
GRDEV_ROTATE_180 = 2,
GRDEV_ROTATE_270 = 3,
};
enum {
/* flip states; we treat this as abelian group V4 with XOR */
GRDEV_FLIP_NONE = 0x0,
GRDEV_FLIP_HORIZONTAL = 0x1,
GRDEV_FLIP_VERTICAL = 0x2,
};
/*
* Displays
*/
struct grdev_fb {
void *maps[4];
};
struct grdev_display_target {
uint32_t x;
uint32_t y;
unsigned int rotate;
unsigned int flip;
};
const grdev_display_target *grdev_display_next_target(grdev_display *display, const grdev_display_target *prev, uint64_t minage);
void grdev_display_flip_target(grdev_display *display, const grdev_display_target *target, uint64_t age);
(_t); \
/*
* Events
*/
enum {
};
struct grdev_event {
unsigned int type;
union {
struct {
struct {
};
};
/*
* Sessions
*/
enum {
GRDEV_SESSION_CUSTOM = (1 << 0),
};
unsigned int flags,
const char *name,
void *userdata);
/*
* Contexts
*/